Pressure head for veneer lathe



July 3l, 1951 W. .1. MILLER ET AL PRESSURE HEAD FoR VENEER LATHE 2 Sheets-Sheet l Filed Aug. 50, 1946 July 31, 195] Filed Aug. 30, 1946 W. J. MILLER I'AL PRESSURE HEAD FOR VENEER LATHE 2 Sheets-Sheet 2 HTTORNE Y Patented .uly 3l, 1951 UNITED STATES PATENT OFFICE PRESSURE HEAD Fon-VENEER LATHE William J. Miller and Alfred.C...ohnson, Seattle, Wash., assignors to ElliottBay Mill Co., Seattle, Wash., a corporation of Washington Application August 30, 1946,r Serial No. 693,930

This invention relates to a pressure head or cap for a veneer lathe.

In a veneer lathe a pressure head or cap of the type herein disclosed isY used as -a mounting'means for a pressure bar thatA engages with and is pressed against a rotating log a short distance inv advance of a knife that peels veneer off of the log. These pressure heads are of .a length greater than the width of the veneer being peeled, are of relatively strong, rigid metal construction, are relatively heavy and must be capable of accurate adjustment in order to properly hold the pressure bar against the work.

An object of this invention is to provide a pressurehead. or cap that is particularly well adapted for use in connection with a double roller pressure bar of the form. disclosed in our copending lciatent application Serial Number 623,706, led October 22, 1945, said head supporting the double roller pressure bar in such a man-ner that the pressure bar is readily' accessible.

Another object of this invention is to provide? a pressure head or cap for a veneer lathe which isadjustably supported at -four points so that either end of said head or cap or either the rear or the front edge of said head orv cap can be adjusted either up or down.

Another object is to provide a pressure head or cap having a shelf extending along its forward edge on which a roller pressure bar rests and is supported; the space above said pressure bar being open and unobstructed to provide easy access to said pressure bar.

-Another object of this invention is to provide ai. pressure head or cap for a veneer lathe that can. be quickly and easily withdrawn from or moved towardA a log which is being peeled Iand that also has a ne adjustment operable to regulate the pressure against the log of a pressure bar which is carried by said pressure head.

Other objects of this invention will be apparent from the following. description taken in connection with the accompanying drawings.

In the drawings Figure l isv a fragmentary top plan view of' pressure head or cap constructed in accordance with this invention, the pressure bar being omitted and parts of the frame which supports the cap being broken away.

Fig. 2 isa fragmentary rear elevation of the pressure head or cap shown in. Fig. l, parts of the head:v supporting frame being broken away.

Fig'. 3 is an end view with parts in section of Said. head orcap taken substantially on broken line 3--3 of Fig. l and on` alarger scale than Figs.

4 Claims. (Cl. 144--213) 2 Y l and 2, a pressure bar being shown in said Fig. :3.

Fig. 4 is a sectional View, on a larger scale tl'lahr Fig- 1, taken through said head substantially on a broken line 4 4 of Fig. 1, the pressure bar being omitted.

Fig. 5 is a detached fragmentary sectional view showing parts of the mechanism used to retract the pressure head or cap and to adjust the posi tion of the same. 'f

Like reference numerals designate like par throughout the several views.

This pressure head or cap comprises a relatively long metal body portion I0 of generally semi circular cross sectional shape, see Fig. 4. 'The body portion I0 is provided with two end Walls I I,

see Fig. l, and with a plurality of spaced apart transverse stiiening ribs or partitions I2.

At its forward side, shown at the right in Figs. 3 and 4, the body portion I0 is provided with an upright wall I3 and with an outwardly protrud-A ing shelf I4 that is substantially horizontal. The upright wall I3 and outwardly protruding shelf I4 cooperate to provide an L-shaped pressurebar receiving groove at the front of the body portion I0. A pressure bar 9, Fig. 3, which may be of the type disclosed in our copending application hereinbefore referred to, is supported on the shelf HI.` Throughout the major part of the length of the body portion I0 the shelf I4 tapers to a substantially sharp forward edge I5 by reason of an irrclined bottom wall VI 6. However, at the two ends of the body portion II the horizontal shelf I4 is wider toward its forward edge to provide a supporting surface Il that is substantially parallel with the top surface of said shelf. This sup porting surface I'I preferably has a groove I8 therein for engagement with a spline I9 on a` bronze bearing plate 20. The bronze bearing plate 20 at each end of the pressure head is secured to the head and rests upon .a at surface 2I of an inclined adjuster member 22. Each in= clined adjuster member 22 is slidably and adjustably supported on an inclined surface 23 of a fixed frame 24 commonly termed a knife casting, see Figs. l, 2 and 3.

Each inclined Iadjuster member is longitudii' nally adjustable along its inclined supporting surface 23 by screw means. This screw means may comprise a screw 25 threaded into the inclined adjuster member 22 and rotatively supported by a bearing lug 26A that is rigid with the fixed frame 24. Each screw 25 has a thrust collar 21 that bears against the lug 26 and each screw 25 is provid-ed ywith means,fsuch as a hexagonal head V28,V

by which it may be turned. Turning one of the screws 25 longitudinally moves the meinbei" 22 that is connected therewith and vertically adjusts one forward corner of the body portion I0.

The bearing plates 20 are secured to the shelf portions |4 and are supported by and slidably movable on the flat surfaces 2| of members 22. Thus in addition to providing for vertical adjustment, the supporting means for the forward edge portion of the pressure head allows said pressure head to be slidably moved forwardly and rearwardly and allows the forward edge portion of said pressure head to be lifted vertically off of its supports. The hereinafter described supporting means for the rear edge portion of the pressure head permits said head to be slidably moved forwardly and rearwardly or to be tiltingly moved so as to elevate the forward edge portion of said head.

The rear portion of the pressure head is provided at each end with two vertically spaced apart rearwardly projecting integral lugs 30 by means of which the rear portion of the pressure head is supported. Each pair of lugs 30, have opposed surfaces 3| which are inclined relative to each other, said surfaces 3| being divergently inclined in a direction from front to rear of said pressure head.

. Two adjustable tapered wedge members 32 are provided between each pair of lug mem-bers 30 in slidable engagement with the inclined surfaces 3|. The opposed faces 33 of each pair of wedge members 32 are parallel to each other and form trackways for the reception therebetween of a cross head block 34. A strong and rigid mounting shaft 35 is positioned to the rear of the body portion and extends parallel therewith through the two cross head blocks 34. The respective end portions of the shaft 35 are supported for oscillation in bearings 36 that are rigid with the xed frame members 24 at opposite ends of the pressure head.

The wedge members 32 are longitudinally adjustable and provide means for vertically adjusting the cross h-ead blocks 34 to thereby vertically adjust the rear edge portion of the pressure head. Preferably each wedge member 32 has a rear end flange 31 that extends sidewise from the member 32 and is perforated to t over one or more stud bolts 38 that are rigid with the lugs 30. Two nuts 39 on each stud bolt provide means for longitudinally adjusting each wedge member. To adjust a cross head block vertically it is necessary to move, in opposite directions, the two wedge members 32 between which said cross head block is supported.

Plates 40 are secured to the sides of the lugs 30 to prevent sidewise displacement of the wedge members 32 and cross head blocks 34.

From the foregoing description it will be apparent that the pressure head is supported at the four corners by four independently adjustable devices thus making it possible to adjust either end or either edge of said pressure head up or down or to independently adjust any corner of said pressure head in the event such corner adjustment is needed. The pressure head is of generally rectangular shape in plan and each corner of the same is supported by an independent vertically adjustable supporting means.

Devices for imparting a parallel movement to the pressure head toward and away from the Work are provided in duplicate at the two ends of said pressure head. These devices are interconnected for simultaneous movement by the mountingshaft 35.

These pressure head moving devices at each end of the pressure head each comprise a horlzontal lever 4|, Fig. 3, having a hub member 42 that is secured by a key 43 to the mounting shaft 35. Preferably an upright lever 44 is rigidly connected with at least on-e of the hub members 42 and is connected by a rod 45 with a piston 46 in a pneumatic cylinder 41. The pneumatic cylinder 41 and piston 46 are used to impart oscillation to the shaft 35. Each lever 4| is connected by a pivot 48 with one end of a link 49. The other end of each link 49 is connected by a pivot 5|] with a member 5| that forms part of an adjustable connection with the body portion I8 of the pressure head. The member 5| is supported for longitudinal movement between guide blocks 52 that are rigid with the adjacent end wall of the pressure head and are preferably adjustable.

The member 5| has a threaded stern 53 that is threaded into a sleeve 54, Fig. 5. The sleeve 54 has an integral worm wheel 55 on one end thereof. A bearing bracket 56 is secured as by cap screws 51 to the adjacent end wall I of the pressure head to support the sleeve 54. Two thrust bearings 58 in the bracket 56 cooperate with the bracket 56 and worm wheel 55 and with a collar 59 on the sleeve 54 to support said sleeve 54 so that said sleeve is freely rotatable but can not be moved longitudinally relative to the adjacent pressure head end wall The worm wheels 55 at the two opposite ends of the pressure head are interconnected for simultaneous rotary movementibya shaft 60 having thereon two Worms 6| that mesh with the respective worm wheels. The shaft 6D extends from one end to the other of the pressure head and is provided with suitable means by which it may be turned either manually or by the application of mechanical power. As illustrative of one means for turning the shaft 6U said shaft may be pro-l vided with a sprocket wheel 62 carrying a link belt 63.

To provide clearance for retracting the pressure head away from the work and toward the shaft 35 and cross head blocks 34 said pressure head is preferably provided with a shallow longitudinally extending indentation 64, Fig. 4, in alignment with the shaft 35 and with two deeper indentations 65, Fig. l, in alignment with the blocks 34.

Rotation of shaft 60 will operate .through worms 6|, worm wheels 55, sleeves 54, stems 53,`

members 5|, links 49, and levers 4| to provide a fine adjustment for moving the pressure bar toward or away from a log B from which veneer is.

being removed. As a quick means for retracting',v

the pressure head away from the log and again moving the same up to the log the mounting shaft 35 can be oscillated .by the pneumatic means 46,.

41 and will impart movement to the pressure head cally and horizontally adjustable head member of generally rectangular shape in plan; four independently operable vertically adjustable pressure head supporting devices slidably supporting said head member for transverse movement and positioned respectively near the four corner portions of said head member and constituting the sole vertical support for said head member; pressure bar means carried by the forward edge portion of said head member; and means for transversely movingsaidvhead member on said four adjustable supporting devices to retract the head member from a log to which it is applied.

2. In a pressure head for a veneer lathe, a relatively long heavy horizontally positioned head member of generally rectangular shape in plan; four independently supported vertically adjustable pressure head supporting devices slidably supporting said head member for transverse movement and positioned respectively near the four corner portions of said head member and constituting the sole vertical support for said head member; pressure bar means carried by the forward edge portion of said lbody member; quickly operable pressure head retracting devices connected with said head member adapted to move said head member on said supporting devices toward and away from a log; and ne ad- .iustment means embodied in said quickly operable head member retracting devices, whereby said head member can be adjusted toward and away from a log.

3. In a pressure head for a veneer lathe a relatively long heavy horizontally positioned head member; two independently operable vertically adjustable supporting devices positioned adjacent the respective ends of said head member and slidably supporting the front edge portion of said head member; a shaft extending along the rear edge portion of said head member; two other independently operable vertically adjustable head member supporting devices positioned near the respective ends of said head member and supported on said shaft and adjustably and slidably supporting the rear edge portion of said head member shaft oscillating means connected with said shaft; and head member moving means connecting said shaft with said head member, whereby said head member will be slidably moved on said supporting devices in directions transverse to its length by oscillating movement of said shaft.

4. In a pressure head for a veneer lathe a relatively long heavy horizontally positioned head member of generally rectangular shape in plan having four corner portions and provided with pressure bar receiving means along its forward edge portion; two independently operable vertically adjustable supporting devices supporting the forward corner portions of said head member for raising and lowering movement, said head member being slidably movable on said supporting devices in directions transverse to its longitudinal axis; a horizontal shaft extending along the rear edge portion of said head member; two cross head blocks pivotally mounted on said shaft adjacent to the respective rear corners of said head member; two .pairs of spaced apart lugs rigid with the respective rear corner portions of said head member, each pair of said lugs being positioned to receive between the two lugs of the pair one of said cross head blocks on said shaft; two tapered wedge members adjustably disposed between the respective lugs of each pair and the top and bottom sides respectively of one of said cross head blocks, each pair of wedge members having two relatively inclined bearing surfaces to provide for vertical adjustment of said head member relative to said shaft in response to longitudinal movement of the wedge members and having two parallel bearing surfaces providing for horizontal movement of said head member relative to said shaft; screw means operable to longitudinally adjust each of said wedge members relative to said lugs and said cross head blocks to thereby vertically adjust the adjacent corner portions of said head member relative to said shaft; shaft oscillating means connected with said shaft; link means connecting said shaft with said head member and operable by rotative movement of said shaft for horizontally moving said head member toward and away from a log; and fine adjustment means interposed in said link means for horizontally adjusting said head member.

WILLIAM J. MILLER. ALFRED C. JOHNSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 149,494 Margedant Apr. 7, 1874 160,372 Wardwell Mar. 2, 1875 198,404 McEachren Dec. 18, 1877 200,996 Fairchild Mar. 5, 1878 347,331 Densmore Aug. 17, 1886 528,120 Brown Oct. 23, 1894 567,153 Morrison et al Sept. 8,1896 771,894 Brumbaugh Oct. 11, 1904 991,414 Barry May 2. 1911 1,989,386 Tallquist et al. Jan. 29, 1935 

